Very unusual.
It is just possible you may have a hardware problem
First try a forced restart
https://support.apple.com/guide/iphone/force-restart-iphone-iph8903c3ee6/ios
If that does not help the next procedure would be to backup then restore your device to factory, and setup the device without restoring a backup, to see if the issue is replicated.
Then restore the backup.
If you need to send the phone in for repair then backing up and restoring to factory would be needed anyway.
Here is a guide for those steps
Backup and restore
(1)How to back up your iPhone, iPad, and iPod touch – Apple Support
Remove SIM PIN if you have set one
(2) Restore your iPhone, iPad, or iPod to factory settings – Apple Support
Set up as new from the Hello Screen without restoring backup. Test if the problem still exists
(3) Restore your iPhone, iPad, or iPod touch from a backup
If that fails arrange a repair under warranty
https://support.apple.com/en-gb/iphone/repair/service